I used my 25' SLX Daz from the ground and it reached about 5 rows of glass above the gutter line on the conservatory.
The roof has a bow on it, I don't know if you spotted that Daz, which leaves a considerable area that cannot be reached form the ground however long the pole is. Which also includes a significant portion of the top shaped glazed area.
We also did the insides as well. Which was fun!